Crushing and grinding machine



1940- D. E. HUGHES CRUSHING AND GRINDING MACHINE 2 Sheets-Shah's 1 Filed April 1, 1940 INVENTOR.

8 Dow E. fiuomfs BY 6 Dec. 31, I. HUGHES 2,227,090

' CRUSHING AND GRINDING MACHINE Filed April 1, 1940 2 Shasta-Sheet 2 INVENT OR.

DON E. Hu HES BY F n/$ 1M A ORNEY5 Patented Dec. 31, 1940 UNITED STATES PATENT OFFICE j CRUSHING AND GRINDING MACHINE Don E. Hughes, Wayland, Mich.

Application April 1, 1940, Serial No. 327,192

This invention relates to improvements in crushing and grinding machines.

The main objects of my invention are:

First, to provide a crushing and grinding machine for milling and the like having improved means for reducing stock to whatever size is desired.

Second, to provide a hammer mill type grinding machine having a comminutlng and grading screen capable of being adjustably positioned with reference to thehousing and crusher bars or hammers therein to enable stock to be reduced to any one of a number of different degrees of fineness.

Third, to provide a machine of the type described, wherein the means for effecting the adjustments mentioned are simple and inexpensive.

Fourth, to provide a machine having an adjustable screen of the type described and means for completely sealing the latter on the grinder housing in any adjusted position thereof.

Fifth, to provide a grinding machine having means for custom grinding stock such as grains and the like to any desired grade or fineness.

Further objects relating to details and economies of my invention will appear from the description to follow. The invention is defined in the claims.

A structure embodying the features of my invention is illustrated in the accompanying drawings, wherein:

Fig. 1 i s a fragmentary view in end elevation illustrating a swinging hammer grinding machine having incorporated therein the features of my invention.

Fig. 2 is a fragmentary view in vertical longitudinal section on line.2--2 of Fig. 1, further 11- lustrating details of the invention.

Fig. 3 is an enlarged fragmentary view in section on line 3-3 of Fig. 2, illustrating structure for clamping the screen in one of its adjusted positions with relation to the grinder housing.

Fig. 4 is an enlarged fragmentary view in section on line 4-4 of Fig. '2, illustrating means for 5 translating the screen longitudinally in the adjustment thereof.

Figs. 5 and 6 are fragmentary views in side elevation illustrating the main features of the invention in two other contemplated embodiments I thereof.

The present invention relates to a grinding and crushing machine of the swinging hammer or hammer mill type such as is commonly used in the milling of grains and for grinding and crushll ing many other articles in processing thereof.

Generally speaking, the invention relates to the provision of a novel type screen for such a machine, which .is adjustable lengthwise thereof and is provided with apertures of. different sizes selectively positionable by the adjustment of the screen to regulate the size or fineness of the ground product and thereby enable custom grinding of grain and the like. More particularly, the invention includes devices of one type or the other for automatically shifting the screen and in positioning the same and in further devices for firmly clamping the same against the sides of the grinder housing so as to completely seal thesame and prevent exit of the ground stock from the housing other than through the-grinding aper- 16 tures. All these instrumentalities are actuable and controllable from a point remote from the machine itself.

. Referring to the drawings, Fig. 1 in general illustrates a grinding and crushing machine of the E0 hammer type including a grinding housing 2 having rotatable hammers 3 of known construction mounted therein. The stock to be ground is led I into this housing in known manner from an upper hopper through a chute 4 past a preliminary 25 crusher ll and magnetic metal separator 42. Many of the details of this machine are entirely conventional and will be recognized as such by those skilled in the art, hence they are not shown in detail nor described with particularity. 0

Referring to Figs. 1 and 2, the housing has the parallel vertical side plates or walls 5 each provided with an arcuate slot 6 to receive the ad justable arcuate screen i for longitudinal adjustment of the latter through the housing. It will be understood that the hammers of the mil coact with this screen in grinding and reducing the stock. As illustrated in Fig.2, the screen 'i' is in reality made up of a plurality of individual screen plates or sections 8 arranged end to end. These individual screens have apertures H] of different sizes therein, the apertures in each individual screen section 8 being of the same size. Likewise, each section or individual screen is of sufllcient length to extend. completely over the space between the housing side walls 5, engaging the latter at the ends of the sections so as to enclose the-housing.

At its lateral sides, the elongated composite. screen I is secured by tapered pins 9 to the. 00111. 5 bined rail and rack bars II, I! which have rack teeth l3 engageable by the gears l4, l5 respectively. Each screen section is removably and replaceably mounted on the bars by pins 9, hence a choice is possible as to the character of the individual sections making up the screen as a whole. A smooth rail surface I6 is provided on the bars adjacent and parallel to each set of rack teeth to rollingly support the bars on the spring mounted wheels or rollers ll, 18, which will be further referred to. Bars I I, l 2 are braced at their ends by the angle irons l9, Fig. 2.

.From the foregoing, it will be appreciated that upon rotation of gears l4, l5 the screen 1 is translatable longitudinally of the machine on rollers l1, l8 to position any desired one of the screen sections or elements 8 across the grinding housing. The screen is resiliently carried by and elevated slightly by the rollers to prevent binding of the screen with the lower side of the slots 5 through which -it travels.

The gears I 4, l5 are mounted on shafts 20, 2|, respectively, suitably journaled at one side ofthe housing, the shaft 20 being driven from shaft 2|| by means of a link belt drive 22. The shaft 2| is driven from the vertically arranged shaft 23 through meshing bevel gears 24. The shaft 23 ordinarily extends upwardly to a point remote from and usually on a floor above that on which the machine is disposed, this being the conventional practice. Shaft 23 maybe actuated in any suitablemanner as by crank, hand wheel, motor or the like.

It will be understood that rollers ll, l8 lift the screen so that its segmental surface will clear the side walls 5 of the grinding housing at slots 6 without binding. These rollers engage the rail surfaces IE on either side of the housing to lift the screen for translation without, however, disengaging the rack surfaces I3 from the respective gears coacting therewith. To enable this, the rack and gear teeth may be elongated and the slots in the housing side walls 5 made of decreased width or provided with a shoulder 25 adjacent the bars H, l2, so as to restrain the vertical lifting of the screen and prevent its frictional engagement with the upper side of slot 6.

When the desired screening surface is operatively positioned with reference to the housing, I contemplate securely clamping the same over the housing so as to prevent the escape of stock through the slot 6 accommodating the screen. To this end, I provide a pair of arcuate, vertically shiftable clamping bars 26 adjacent and inside either side wall 5 of the housing. Each of these clamping bars has a pair of ears 21, preferably integral therewith, provided with a circular opening and surrounding a circular disk 28 eccentrically secured to a shaft 29. The shafts 29 are located adjacent but spaced from the sides of the arcuate screen 1. The respective shafts are linked together for simultaneous rotation by means of a crank 30 connected to one thereof, a bell crank 3| connected to the other, and a rigid link 32 connecting crank 30 with one arm of the bell crank. The free arm of the bell crank is actuated by a vertically disposed rod 33 from a point adjacent the control for the shaft 23. The operating linkage for clamping the screen is disposed exteriorly of the grinding housing, as illustrated in Fig.1. v Though I prefer the eccentric clamping means shown and described, it will be evident that other equivalent means could well be employed for this purpose.

Immediately adjacent the side walls 5 beneath the arcuate slots 6, there is diposed a pair of arcuate bars 33l, see Figs. 2 and 3, one welded to each side wall and disposed immediately lie-- neath a clamping bar 26 so as to brace and reinforce the side walls 5, as well as provide a surface of considerable width against which the screen can'be clamped without damaging the same. It will be understood that the clamping bars when actuated engage the screen to depress the same against the lifting action of the spring loadedgollers I! and to closely seal the same against the side wall. At the same time, the arcuate bars 26 slidingly engage the portions of the walls 5 ,abovethe screen to close the openings left by the slotsabove the screen, so that escape of ground stock at those points is prevented.

In Fig. 5, I illustrate a modified embodiment of my invention, whereinthe shifting of the screen is accomplished by means of a pair of threaded parallel shafts 34 journaled on a suitable framework 35 and each having a nut 36 threadedly engaging the same, which is mounted on a side rail member 31 secured to the screen. The shafts 34 are connected for simultaneous actuation by a chain belt 38 and are driven from above by a further chain belt 39 or by other equivalent means. On the opposite side of the machine, the rails 31 may be supported for translation by wheels 40.

In Fig. 6, I illustrate a still further modified embodiment of my-invention, wherein the screen supporting structure or frame, which is generally designated 4l, is actuated in either direction by means of cables 42, 43, the latter of which is trained about a pulley on the machine frame. These cables pass around guide wheels 45 and are secured to a pin or lug 46 on the screen frame so as to actuate the screen for translation in an obvious manner when the cables are tensioned. The frame travels on rollers 41 at either side of the housing. 7

The foregoing improvements make it possible for a miller to readily and quickly perform custom grinding on any of several grades demanded most commonly. In thepast, in the event that a different fineness was demanded than the machine was set up to run, it has been necessary to change the screen in its entirety, which is adiflicult and time consuming operation. By the provisions of my invention, change from one grade to another can be effected in an instant. The amount of actuation of the controls (not shown) for a sumcient shifting of the elongated screen requisite to change from one section or area thereof to another may be readily ascertained and suitably calibrated on the control means, thereby rendering it unnecessary to make frequent trips to the machine in adjusting the same. v The aforesaid provisions are simple and inexpensive and can be incorporated in existing grinding machines without seriously altering the same.

I have illustrated and described my improvements in embodiments which are very practical. I have not attempted to illustrate or describe further embodiments or adaptations as it is believed that this disclosure will enable those skilled in the art to embody or adapt my improvements as may be desired.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a grinding machine of the swinging hammer type having a housing wherein hammers are rotatably mounted, an elongated arcuate screen having a plurality of longitudinally disposed sec- .tions thereof provided with grinding and grading apertures of different sizes, the apertures in a given section being of the same size, said housing having side walls provided with arcuate slots receiving the screen with substantial vertical clearance for longitudinal translational adjustment ing said rails to elevate the screen to clear the slot when the screen is translated, and means for clamping the screen on the housing in adjusted position thereof and for sealing the openings afforded by the clearance of the slots, comprising a pair of arcuate clamping bars disposed interiorly of the housing in sliding engagement with the side walls thereof, and eccentrc means rotatably mounted in the side walls and connected to said arcuate bars for actuating the latter vertically to engage and clamp the screen against the housing in the translationally adjusted position of the screen, said bars closing the opening afforded by said slots not occupied by the screen.

2. In a grinding machine of the swinging hammer type having a housing wherein hammers are rotatably mounted, an elongated arcuate screen having a plurality of longitudinally disposed sections thereof provided with grinding and grading apertures of different sizes, the apertures in a given section being of the same size, said housing saving side walls provided with arcuate slots receiving the screen with substantial vertical clearance for longitudinal translational adjustment of the screen with reference to the housing, means for actuating the screen for translational adjustment to selectively position said sections relative to the housing and hammers, comprising a pair of rack bars secured to the opposite side edges thereof, gears rotatably mounted on the frame' of the machine and meshing with said rack bars and means for rotating said gears from a point remote from the machine, and means for clamping the screen on the housing in adjusted position thereof and for sealing the openings afforded by the clearance of the slots, comprising a pair of arcuate clamping bars disposed interiorly of the housing in sliding engagement with the side walls thereof, and means connected to said arcuate bars for actuating the latter vertically to engage and clamp the screen against the housing in the translationally adjusted position of the screen, said bars closing the opening afforded by said slots not occupied by the screen.

3. In a grinding machine of the swinging hammer type having a housing wherein hammers are rotatably mounted, an elongated arcuate screen having a plurality of longitudinally disposed sections thereof provided with grinding andgrading apertures of different sizes, the apertures in a given section being of the same size,

said housing having side walls provided with arcuate slots receiving the screen with substantial vertical clearance for longitudinal translational adjustment of the screen with reference to the housing, means for actuating the screen for translational adjustment to selectively position said sections relative to the housing and hammers, spring means engaging said rails to elevate the screen to clear the slot when the screen is translated, and means for clamping the screen, on the housing in adjusted position thereof and for sealing the openings afforded by the clearance of the slots, comprising a pair of arcuate clamp ing bars disposed interiorly of the housing in sliding engagement with the side walls thereof, andeccentric means rotatably mounted in the side walls and connected to said arcuatebars for actuating the latter vertically to engage and clamp the screen against the housing in the translationally adjusted position of the screen, said bars closing the opening afforded by said slotsnot occupied by the screen.

' 41 In a grinding machine of the typedes'cribed having a housing wherein hammers are rotattably mounted, an elongated arcuate screen having a plurality of longitudinally disposed sections thereof provided with grinding and grading apertures of different sizes, saidhousing having side wallsprovided with arcuate slots receiving the screen with substantial vertical clearance for longitudinal translational adjustment of the screen with reference to the housing, means for actuating the screen for translational adjustment to selectively position said sections relative to the housing and hammers, and means for clamping the screen on the housing in .adjusted position thereof and for'sealing the openings afforded by the clearance of: the slots, comprising a pair of arcuate clamping bars disposed interiorly of the housing in sliding engagement with the side walls thereof, and means connected to said arcuatebars for actuating the latter vertically to engage and clamp the screen against the housing in the translationally adjusted position of the screen, said bars closing the opening afforded by said slots not occupied by the screen.

5. In a grinding machine of the type described mounted, an elongated arcuate screen having a plurality of longitudinally disposed sections thereof provided with grinding and grading apertures of different sizes, said housing having side walls provided with arcuate slots receivingthe screen for longitudinal translational adjustment of the screen. with reference to the housing, means for actuating the screen for translational adjustment to selectively position said sections relative to the housing and hammers, and means for clamping the screen on the housing in adjusted position thereof, said last named means slidably engaging the side Walls above the screen and closing the opening afforded bys'aid slots not occupied by the screen.

6. In a grinding machine of the rotating hammer type having a housing wherein the hammers are rotatably mounted, an elongated arcuate screen having a. plurality of areas thereof provided with grinding and grading apertures of different sizes, said housing having'side walls provided with arcuate slots receiving the screen for selective longitudinal adjustment of the areas "of the screen with reference to the housing, means prising a rack bar secured to the screen, a gear rotatably mounted on the frame of the machine and meshing with said rack bar, and means for rotating said gear, and means for clamping the screen on the housing in adjusted position.

7. In a grinding machine of the rotating hammer type having ahousing wherein the hammers are rotatably mounted, an elongated arcuate screen having a plurality of areas thereof provided with grinding and grading apertures of different sizes, said housing having'side walls provided with arcuate slots receiving the screen for selective longitudinal adjustment of the areas of the screen with reference to the housing, means having a housing wherein hammers are rotatably 60 for actuating the screen for said adjustment comone another for receiving the screen, means operfor actuating the screen for said adjustment comprising threaded means secured to the screen, an elongated screw rotatably mounted on the frame of the machine and threadedly eng ing said last named means, and means for rotating said screw, and means for clamping the screen on the housing in adjusted position.

8. In a grinding machine of the rotating hammer type having a housing wherein the hammers are rotatably mounted, an elongated :arcuate screen having a plurality 01' areas thereof provided with grinding and grading apertures of dii'erent sizes, said housing having side walls provided with arcuate slots receiving the screen for selective longitudinal adjustment of the areas oi! the screen with reference to the housing, means for actuating the screen for said adjustment comprising flexible cable means secured to the screen, and means for actuating said flexible cable means in opposite directions to actuate the screen oppositely, and means for clamping the screen-on the housing in adjusted position.

9. In a grinding machine having a housing and a grinding member operatively mounted in the housing, an elongated arcuate screen shii'tably mounted on the housing and adjustable with reference to the housing to longitudinally position difl'erent areas of the screen selectively relative to the housing, said housing having side walls provided with arcuate slots axially alined with able at a point remote from the machine to longitudinally adjust the screen to selectively position said areas, and means for clamping said screen against said side walls at the slots therein when the screen is in longitudinally adjusted position.

10. In 'a grinding machine having a housing and a grinding member operatively mounted in the housing, an elongated arcuate screen shiftably mounted on the housing and adjustable with reference to the housing to longitudinally posiarcuate slots axially alined with one another for receiving the screen, means to adjust the screen,

and means for clamping said screen against said side walls at the slots therein when the screen is in adjusted position.

DON E. HUGHES. 

